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Dirhenium decacarbonyl may be obtained by reductive carbonylation of rhenium(VII) oxide (Re 2 O 7) at 350 atm and 250 °C. [4] Re 2 O 7 + 17 CO → Re 2 (CO) 10 + 7 CO 2. It can also be prepared by the reaction of a methanol solution of sodium perrhenate and carbon monoxide at 230 °C and 115 atm. [9]
O ratio is also used to predict barrel life in cartridges of the same caliber, but not of different calibres, since the ratio is an extensive quantity that does not correlate to temperature or pressure (e.g. a .50 cal straight cartridge may have the same overbore as a highly necked down .17 cal cartridge).
120×570mm NATO tank ammunition (4.7 inch), also known as 120×570mmR, is a common, NATO-standard (STANAG 4385), tank gun semi-combustible cartridge used by 120mm smoothbore guns, superseding the earlier 105×617mmR cartridge used in NATO-standard rifled tank guns.
This caused many existing toy gun products on the Chinese market (particularly airsoft) to become illegal overnight, as almost all airsoft guns shooting a standard 0.20 g (3.1 gr) 6 mm (0.24 in) pellet have a muzzle velocity over 76 m/s (250 ft/s), which translates to more than 0.58 J (0.43 ft⋅lbf) of muzzle energy, or 2.0536 J/cm 2 of "ratio ...
The rimmed cartridge, sometimes called flanged cartridge, is the oldest of the types and has a rim that is significantly larger in diameter than the base of the cartridge. Rimmed cartridges use the rim to hold the (usually straight sided) cartridge in the chamber of the firearm, with the rim serving to hold the cartridge at the proper depth in ...
Most rifle cartridges have a high load density with the appropriate powders. Rifle cartridges tend to be bottlenecked, with a wide base narrowing down to a smaller diameter, to hold a light, high-velocity bullet. These cases are designed to hold a large charge of low-density powder, for an even broader pressure curve than a magnum pistol cartridge.
Perrhenic acid (H 4 Re 2 O 9) adopts an unconventional structure. The most common oxide is the volatile yellow Re 2 O 7. The red rhenium trioxide ReO 3 adopts a perovskite-like structure. Other oxides include Re 2 O 5, ReO 2, and Re 2 O 3. [35] The sulfides are ReS 2 and Re 2 S 7. Perrhenate salts can be converted to tetrathioperrhenate by the ...
The Hécate II is the standard heavy sniper rifle and anti-materiel rifle of the French Army, sometimes known as the FR-12.7 (French: Fusil à Répétition de calibre 12.7 mm or "12.7 mm calibre repeating rifle").